The goal of the MBL Neurobiology Course is to provide students who are likely to become creative and productive neurobiologists with an intensive course in Molecular and Cellular Neurobiology, taught by leading scientists in the field. It is an intensive and comprehensive, laboratory-oriented course which has been offered every summer for the past 31 years at the Marine Biological Laboratory in Woods Hole, Massachusetts, with continuous NIH support for the past 20 years. The course duration is nine weeks, from mid-June to mid-August, and is divided into three sections: 1) Electrophysiology, 2) Molecular Neurobiology, and 3) Microscopy and Imaging. Topics explored in depth include structure/function analysis of voltage-gated and ligand-gated ion channels, second messenger-mediated cell signaling, synaptic transmission, neuromodulation and integration, nerve cell biology, the cytoskeleton and neurite outgrowth, and neural plasticity. In addition, the course organizes special evening lectures by visiting scientists. Students also present short seminars concerning the research they are pursuing at their home institutions. At the end of each section, they present the results of their research projects. As the course continues to meet a national need for the training of graduate and postdoctoral students, it offers students the opportunity to work with internationally recognized experts in neurobiology, using state-of-the-art equipment. The goal of the course is to bring students to the forefront of knowledge in Molecular and Cellular Neurobiology, imparting a theoretical understanding of significant unsolved problems and the experimental tools and approaches that will be useful in solving them. Integrating the three neurobiology sections allows the students to design multidisciplinary projects under the mentoring of internationally renowned scientists. Funding is requested to continue this unique, nationally prominent training opportunity, which represents a sound investment for our scientific future.